Now I have to take another drink! Read these:
"Grading for Mixed Delivery: Cinema, Home, and Every Screen in Between" by Cullen Kelly
https://blog.frame.io/2019/10/14/gradin ... -delivery/and
"How to Deal with Levels: Full vs. Video"
by Dan Swierenga
https://www.thepostprocess.com/2019/09/ ... l-vs-videoand I think both cover the issues and the solutions very well.
Understanding color management is also helpful:
"Color Management for Video Editors"
https://jonnyelwyn.co.uk/film-and-video ... o-editors/ The above articles will explain why things change on different displays, different playback engines, and the importance of calibration and color-managed outputs.
I generally try to export a second or two of SMPTE Bars at the head of the project, and I import the file back into Resolve to check it on scopes to verify all the levels are correct. Using calibrated displays is a must -- without that, you have no idea what you're looking at. We also accept that the basic picture is going to change a little bit on different devices, because that's life.